Effects of interparticle friction on the response of 3D cyclically compressed granular material

TL;DR

This study investigates how inter-particle friction influences the deformation and shear band formation in 3D granular materials under cyclic pure shear, highlighting the role of friction in particle rotations and localization.

Contribution

It provides new insights into the impact of varying inter-particle friction on shear band thickness, particle rotation localization, and displacement distributions in 3D granular systems.

Findings

Higher friction leads to thinner, more pronounced shear bands.

Particle rotations become localized in shear zones at high friction.

Rotation amplitudes are homogeneous at low friction, independent of translations.

Abstract

We numerically study the effect of inter-particle friction coefficient on the response to cyclical pure shear of spherical particles in three dimensions. We focus on the rotations and translations of grains and look at the spatial distribution of these displacements as well as their probability distribution functions. We find that with increasing friction, the shear band becomes thinner and more pronounced. At low friction, the amplitude of particle rotations is homogeneously distributed in the system and is therefore mostly independent from both the affine and non-affine particle translations. In contrast, at high friction, the rotations are strongly localized in the shear zone. This work shows the importance of studying the effects of inter-particle friction on the response of granular materials to cyclic forcing, both for a better understanding of how rotations correlate to translations in sheared granular systems, and due to the relevance of cyclic forcing for most real-world applications in planetary science and industry.